Shot shell with shot having differential lubrication



Jul 19, 1966 S. A. LOUKOMSKY SHOT SHELL WITH SHOT HAVING DIFFERENTIAL LUBRICATION Filed Sept. 1, 1964 INVENTOR.

SERGE A. LOUKOMSKY BY W 52mm,

774m,T: /M 04M.

ATTORNEYS fradial streaks.

yet easily distributed.

United States Patent p H 3,261,292 SHOT SHELL WITH SHOT HAVING DIFFERENTIAL LUBRICATION Serge A. Loukornsky, Flippin, Ark. Filed Sept. 1, 1-964, Ser. No. 393,712 6 Claims. (Cl. 102-42) The understanding of the results of my invention is facilitated-by a consideration of shot shells heretofore used as exemplified by patterns of ordinary shells, free from appreciable gas leakage around the wad column, when they are loadedwith pellets of progressively increasing lubricity.

This progressive increase of lubricity of pellets can be achievedjbylrolling unlubricated pellets chilled shot coated with vinyl chloride (or another coating of low lubricity) with increasing amounts of graphite.

Patterns produced by shells loaded with unlubricated .shot have' strong centers of dubious distribution, are clumpy, and have unreliable edges consisting mainly of I call this type of pattern-Type 1. As the lubricity of pellets is increased there is a gradual improvrnent of distribution and evenness. Fairly even patterns are obtained at a certain point. I call this type of pattern-Type 2. A further increase of lubricity first weakens the center, and finally produces blown patterns. I call: this type of patternType 3.

7 As a result of extensive investigations I have discovered a means of avoiding Type 1 patterns without the danger of approaching conditions producing Type 3 patterns.

I have further discovered means of controlling pattern "density keeping barrel, basic shell, and weight of shot invariant, without compromising the evenness. In ac- 'cordance with my invention I lubricate the shot in the shell so as to effect lubrication characteristics which I shall refer to as controlled diiferential lubrication, or

C.D.L. The C.D.LL is provided by applying one or more ,lubricants to the shot so that there is a difference in the effective lubricity of the forward part and the rearward part of the shot load of the shell.

I may provide C.D.L. in one of'several lubrication systems: Inaprefen'ed system all pellets are first coated with the same resin, and then lubricated so that, for example, the shot of the forward part of the shot load may contain the same kind of lubricant but in different amount than the shot in the rearward part of the shot load. Al-

ice

ternatively only the rearward part of the shot load may be lubricated, or the two parts lubricated with difierent lubricants producing surfaces of different coeflicients of friction. I may also coat the front and rear parts of the shot load with coatings of difierent lubricity and either dispense with further lubrication or use additional lubricants as needed. C.D.L. according to my invention results in obtaining a lower amount of lubrication in the forward part of the shot charge than in the rearward part of the shot charge. This differential has to be accurately controlled. There is a sharp plane of division between the two parts. The location of this plane is fixed by the differential of lubrication of the two parts of the shot load.

The rearward part may vary from two layers of shot to 60% of the shot charge. In a preferred shell the rearward and forward parts are of equal mass.

I may use various kinds of surface coatings on the pellets, such as lacquers, and different resins (applied in solution form), and for additional lubrication effects I use waxes, or dry lubricants. For dry lubricants I prefer'to use mica, graphite, and various water insoluble metallic salts of long chain aliphatic acids. Waxes and organic lubricants can be used to either increase or decrease the lubricity of a part of the shot charge.

Examples of shot loads for different shot shells of the invention are described in the following tables.

Table 1 gives examples of 1% ounce loads of chilled shot for a regulation 12 gauge trap shell.

Table 2 gives examples of 1% ounce loads of chilled shot for a standard maximum load 12 gauge shell.

Both tables illustrate three lubrication systems:

System 1: Same basic pellets are used for both parts of the shot load. Different amounts of the same lubricant are used for the front and back parts of the shot charge.

System 2: Same basic pellets for both parts. Different lubricants for front and back parts.

System 3: Different basic pellets for the two parts.

Table 1 also illustrates shells giving even patterns of a wide range of densities.

Since the amounts of lubricant in some cases are quite small, the direct application of these small amounts can be erroneous, since the lubricant can be lost in some crev- TABLE 1 [Shot loads (1% oz.) for basic 12 gauge trap shells] Rear Part Front Part a Rear Lubri- Shot Part, cation Size Percent Lubricant, Lubricant, Type of Shell and Remarks System of Total Basic Coat l Grains per Basic Coat 1 Grains per Pound and Pound and Kind Kind 7% Vinyl chloride Vinyl chloride Sl. clumpy.

d }Handicap trap.

l6 yd. trap.

7% Hunting-cven, fairly open.

7% do Handicap trap.

6 Alkyd (Hareo spray enamel), None High densityvery even.

not rolled. Light field load.

3 GR Graphite.

Dixon Mycrofync. Powdered Mica.

4 Two layers.

Reardon products Drylubc. It is particularly suitable for lubrication of front part of shot load being less slippery than graphite TABLE 2 [Shot loads (1% oz.) for high velocity 12 gauge shells] Rear Part Front Part Rear Lubri- Shot Part, cation Size Percent Lubricant, Lubricant, Type of Shell and Remarks System of Total Basic Coat 1 Grains per Basic Coat 1 Grains per Pound and Pound and Kind Kind 6 25 NC. lacquer .22 GR N.C. Lacquer .06 GB High density. 6 25 d .22 GR." do .10 DL High density. 2 7% 4 34 Epoxy, 3 not r0lled None Harco enamel, not rolled None Medium high density.

1 Plasticized Nitro Cellulose lacquer-Co0ks Industrial lacquer.

2 These shells have been subject to extensive storage tests, as Well as shot at temperatures from +110 F. to F.

3 EpoxyC0oks Timbertone varnish. 4 Three layers.

Table 1 illustrates two important factors:

(1) The lubrications of the rear and front parts must be matched. This controls the distribution of the patterns.

(2) The overall lubrication level of the shot charge controls the density of the pattern.

The first factor is critical, the second is not. The percentage tolerance on the amount of lubricant in any one of the parts if the other is not changed is a function of the size of the part the lubrication of which is being varied. It is 10% for equal masses of front and rear parts. It is for the rear part if that part is of the shot charge.

The dry lubricants used for the lubrication of the shot charge in the shells of this invention are always used at a starvation level. All the dry lubricant adheres firmly to the surface of the shot and none is loose. The required differential lubrication for a match in different shells is a function of wad effect. The required differential of lubrication in loads with strong wad effect is less than it is for loads with low wad effect as for instance trap loads. C.D.L. shell for any gauge or load are developed by adjustment of the lubrication of one of the parts of the shot charge. To do this it is necessary to interpret patterns resulting from deviations from a match:

(1) A match produces an even pattern. If this pattern is too dense or not dense enough it cannot be corrected without changing the overall lubrication level.

(2) An underlubricated pattern can exist at all lubrication levels. This means that the center is stronger than the edges, and that the rear of the shot charge should be lubricated more, to obtain an even pattern.

(3) An overlubricated pattern means that the rear of the shot charge is lubricated too much (for an invariant front) to give an even pattern. Patterns of this type have a weakened center and strong edges.

When a match is obtained for an overall lubrication level near optimum, quite unexpected results are obtained: The density in a 20 inch circle at 40 yards can be increased by as much as 50% of that of the single shot load value. The gain in a inch circle at yards may be over 20% (from around 70% to over 90% of total).

On the other hand when matches at high lubrication levels are used, excellent open patterns are obtained. Modified chokes are particularly adept to produce even patterns of different densities, with the shells of my invention: (from to 90%). Excellent results are obtained from skeet bore to extra full choke using the same shells. Special shells can be made for extra full chokes.

It has been found desirable to apply dry lubricants to pellets having a basic coating of resin or lacquer rather than to uncoated polished and cleaned pellets. The reason for this is two fold:

.(1) A delicate match is required between the rear part and the front part of the shot load. A shell with such a pellet load must use pellets that are protected from corrosion.

(2) If pellets are not coated their surface is not well defined. Uncoated pellets often have pitted surfaces even when polished.

The coating of pellets with solutions of resins while practiced in industry is described, because the process is critical.

In applying resin coatings on the pellets, the amount of resin should be such, that agglomerates of pellets after drying should be easily broken up leaving only evidence of point contact. Standard resin coating should be thinned with solvent by a factor of about 2 /2. This resin solution should be applied to clean pellets by rolling or by spraying While rolled. The wet pellets should be rapidly dumped on a drying screen and dried without rolling. Single component lacquers or resin solutions requiring no air curing are preferred to avoid complications in drying. Coated pellets should not scuff or peel when rolled. They should pick up dry lubricants and distribute them evenly when rolled.

There is a factor, which is far from obvious, that has been uncovered in my investigations. Some coated pellets acquire unstable surfaces when rolled. Such pellets exhibit a change in their lubricity when stored after rolling. For instance, pellets coated with Harco spray enamel, should not be used without aging after being rolled with or without dry lubricants to adjust their lubricity.

My invention while effective in improving trap shells, is particularly applicable to heavier shot loads and to thin shot columns.

FIG. 1 of the accompanying drawing is a sectional view of a shot shell of the invention. As illustrated, the shot shell comprises a shell 1 of any suitable construction as widely used, a primer 2, a powder charge 3 and a wad 4 over the powder. The shot charge 5 is over the wad 4 and is held in the shell by the top closing disk 6. The shot charge consists of a rearward part and a forward part. The rearward part may consist of but two rows of shot represented by R or any larger amount up to 60 percent of the total shot charge represented by R. The forward part of the shot charge may consist of the part represented by F or any smaller amount represented by F.

I claim:

1. An improved shot shell the shot of which consists of a forward part and a rearward part separated by a plane of division which parts have differential lubrication characterized by the shot of the rearward part having greater lubricity than the shot of the forward part, said rearward part consisting of at least two rows of shot and up to 60% of the total shot.

2. An improved shot shell as defined in claim 1 in which the shot of the rearward part has an applied lubricant which gives the shot more lubricity than the shot of the forward part.

3. An improved shot shell the shot as defined in claim 1 5 in which the shot of the rearward part has a coating of graphite and the shot of the forward part has a coating of graphite in smaller amount.

4. A shot shell as defined in claim 1 in which the rearward and forward parts of shot are about equal in amount.

5. An improved shot shell as defined in claim 1 in which all the shot is .coated with a resin, and the shot in the rearward part of the shot load has an applied dry lubricant.

6. An improved shot shell the shot of which consists of two parts, a rearward part consisting of at least two rows of shot and up to 60% of the total and the remainder a forward part in which the rearward part has a coating of a resin and the shot in the forward part has a different resin coating giving it less lubricity than the shot in the rearward part.

References Cited by the Examiner UNITED STATES PATENTS 1,575,716 3/1926 Pavek 102-42 2,772,634 12/ 1956 O'berfell 102-42 2,919,647 1/ 1960 Dear et al 10242 FOREIGN PATENTS 28,372 12/ 1913 Great Britain.

BENJAMIN A. BORCHELT, Primary Examiner. R. V. LOTTMANN, Assistant Examiner. 

1. AN IMPROVED SHOT SHELL THE SHOT OF WHICH CONSISTS OF A FORWARD PART AND A REARWARD PART SEPARATED BY A PLANE OF DIVISION WHICH PARTS HAVE DIFFERENTIAL LUBRICATION CHARACTERIZED BY THE SHOT OF THE REARWARD PART HAVING GREATER LUBRICITY THAN THE SHOT OF THE FORWARD PART, SAID REARWARD PART CONSISTING OF AT LEAST TWO ROWS OF SHOT AND UP TO 60% OF THE TOTAL SHOT. 